Re: "Standard" or proven 155-gr Palma loads?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grump</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Downzero</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Grump</div><div class="ubbcode-body">
Question--can Quickload calculate pressure with the bullet at "X" inches down the bore? I know what values to look for, and am wondering if that program would be worth looking into for this M1A exercise.
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You really shouldn't be concerned about something like this. The M14 was designed for a 147 grain bullet at about 2600 FPS with a particular burn rate of power.
The further you deviate from that, in bullet weight or velocity, the greater your chance will be of damaging your rifle.
If you want to hot rod a rifle, get an AR or a bolt gun. Hot rodding the M14 or M1 will result in damage to the rifle and/or your face. </div></div>
Yeah, yeah, yeah. Have you ever SEEN any testing results showing port pressure?
NRA did some back in the 1980s and you can find the results if you care to educate yourself. Interestingly enough, the highest port pressures (near the max of the tolerances) were with Sierra 150-gr Matchkings, and the lower port pressures using the same powders were with 168-gr and either 173- or 180-gr bullets.
Chamber pressures were NATO-safe for all loads.
Put that in your pipe and smoke it.
I already have some data points on this and am NOT planning on hot-rodding loads in the M1A. One powder seemed to max out both chamber pressure and port pressure (based on ejection pattern about = op rod speed = usually correlates with port pressure) at a whopping 2760 fps with 155s. I broke down the test loads above that. </div></div>
I shoot 168s and 175s in my own rifle, so obviously it is not the bullet weight to which I refer.
It is the combination of slow powders and maximum loads that will destroy one of those rifles in short order.
The military shot 173 grain bullets in M1s; It's obviously not the bullet weight that concerned them. It's not even the pressure--plenty of safe loads do not exceed NATO pressures and will still be very hard on the gun.
The M1A is just like the M1. Stick to powders that are similar to what the military loaded for it and load to modest pressures or you're asking for trouble.
